National Library of Scotland Curator Robert Betteridge inspects the Robert Burns manuscripts. Picture: Greg Macvean

Part of the world’s single largest collection of handwritten poems and letters by Robert Burns has gone on display to the public.

The documents, which were sold to an American before being returned to Scotland 100 years ago, are described as being one of the National Library of Scotland’s “greatest treasures”.

The historic writings have now gone of public display at the National Library of Scotland (NLS) in Edinburgh, along with items that tell the story of how they were controversially sold to America, before being returned to Scotland.

The writings, known as the Glenriddell Manuscripts, feature 27 letters and 50 poems - including well -known works such as Holy Willie’s Prayer - written by the Bard.

Burns penned these for his friend and neighbour Captain Robert Riddell of Glenriddell between 1791 and 1793

Robert Betteridge, the NLS curator who organised the display, said: “This is the single largest collection of Burns’s manuscripts in existence and one of the library’s greatest treasures. Their journey from Dumfriesshire where Burns wrote out the poems and letters, to Liverpool and then the United States is a fascinating one.”

The collection ended up in the possession of the Liverpool Athenaeum, a gentleman’s club in the city, which put them up for auction in 1913 for £5,000 - the equivalent of £333,000 today.

Burns societies and others opposed the sale, but it went ahead, with the manuscripts bought by an American.

They were then sold to John Gribbel, a Burns enthusiast in Philadelphia, who announced in December 1913 he had bought the writings and would be returning them to Scotland.

Mr Gribbel had a special box made to house the manuscripts, with this also among the items included in the exhibition, along with the deed of trust which was drawn up which led to them being permanently housed at the NLS.

Mr Betteridge said the NLS was able to put the historic writings on show only “because of the intervention and generosity of John Gribbel” and added: “It is fitting that we mark the centenary of their gift to the people of Scotland in this way.”